1. Field of the Invention
The present invention relates to tissue typing trays of the type provided with a plurality of wells for microcytotoxic testings and analysis, and, more particularly, to an improved closure for such trays.
2. Description of Related Art
Tissue typing trays typically comprise a box-like construction of conjoining side walls and a bottom, with a plurality of wells disposed on the bottom in an array. Solutions may be introduced into the wells, and testing perform therein. The wells are usually sealed by melting wax around the perimeter of the wells and sealing a well cover thereto in order to prevent evaporation and contamination from the external environment. It also protects user from contents on the tray. A tray cover engages the tops of the side walls in snap-fit closure.
However, the well cover is easily movable laterally, resulting in potential loss of testing reagent and in possible contamination of the contents of one well by the contents of another.